XI - The Synthetic Uses of Grignard Reagents, β-Keto Esters and Diethyl Malonate

Abstract

The reagents that are of particular importance in organic synthesis are Grignard reagents, β-keto esters, and diethyl malonate. Grignard reagents or alkyl magnesium halides behave as a potential source of carbanions. They are nucleophilic reagents and one of their most important uses is to introduce alkyl, alkenyl, or alkynyl groups into molecules containing a suitable electrophilic center. The major uses of Grignard reagents are for the synthesis of alcohols, aldehydes or ketones, monocarboxylic acids, and other organometallic or organometalloid compounds. Methyl magnesium iodide is used analytically for the determination of active hydrogen atoms. The β-keto esters are valuable synthetic reagents for the preparation of ketones and, to a lesser extent, carboxylic acids. Ketones and carboxylic acids are the alternative products of two distinct modes of hydrolytic cleavage that β-keto esters can undergo. Diethyl malonate is widely used for the preparation of monocarboxylic acids, dicarboxylic acids, and β-keto esters. Furthermore, the synthetic applications of diethyl malonate involve its base-catalyzed addition to suitable carbonyl compounds.